For example, a substrate processing process that forms a thin film on a substrate is performed as one process of a method of manufacturing a semiconductor device such as a flash memory or a dynamic random access memory (DRAM). A thin film deposition apparatus, including a reaction chamber that forms respective thin films on a plurality of substrates mounted on a susceptor, is known as a substrate processing apparatus that performs a substrate processing process.
However, the above-described thin film deposition apparatus immediately unloads a substrate from a reaction container when a substrate processing is ended. That is, the thin film deposition apparatus unloads a high-temperature substrate, which is a substrate immediately after film formation process is processed, from the reaction container. Therefore, even after the substrate processing is ended, a thin film formed on the substrate is maintained at a high temperate by the residual heat of the substrate, and thus, an undesired reaction may occur on the thin film. Also, since the crystalline structure of the thin film formed on the substrate is not stabilized immediately after the substrate processing is ended, residual impurities in a processing region are adulterated into the film, and thus, the quality of the film may be degraded. Furthermore, a transfer robot that is used to unload the substrate may be damaged by heat.